In between the engine and your machine, attach any TE energy conduit. TE machines now use RF, which are 0.1x the strength of MJ (though, you generate approx 10x the amount). Machines that use MJ are backwards compatible with RF via energy conduits. They convert between the two, and I suspect the type of energy output is chosen at the interface with the machine.
Thus, it is a good habit to establish a TE energy conduit network and feed any and all machines that utilize RF/MJ through this network. You will have no problems.